It is not possible to give a sensible answer to this question. The highest common factor (HCF) refers to a factor that is COMMON to two or more numbers. You have only one number in the question!
The HCF is 1.
The GCF is 1.
HCF(26, 45) = 1. The numbers are co-prime.
The GCF is 15.
The GCF is 5.
9
It is: 5
15
5
3
It is: 5
The hcf of 12 & 36 is 12